Method for converting encrypted audio stream into PCM codes on high-definition set top box

Abstract

The invention provides a method for converting an encrypted audio stream into PCM codes on a high-definition set top box. The method includes the following steps that 1, before the audio stream is decoded, whether the audio stream and a video steam are synchronous or not is detected; if the audio stream and the video steam are asynchronous, a synchronous mode is adopted so as to guarantee synchronous playing of the audio stream and the video stream, and then a step 2 is performed; if the audio stream and the video steam are synchronous, the step 2 is performed directly; 2, the audio stream and the video steam are distinguished, and if the situation that the audio stream is an encrypted audio steam is found out, an encrypted audio steam conversion PCM module is started; 3, an audio decoder mode is set to be a PCM mode; 4, decryption is performed on the audio stream, the decrypted audio stream is decoded into a PCM code stream, and the PCM code stream is stored into a data buffer; 5, data are read from the data buffer and stored into an audio decoder as so to be decoded and played. The method can achieve synchronization of audio decoding and video decoding during television broadcasting, therefore, the effect that the sound of a high-definition program played by the high-definition set top box for a long time is smooth is achieved and no abnormal phenomenon occurs.

Description

technical field [0001] The invention relates to the technical field of digital television, in particular to a method for converting an encrypted audio stream into a PCM code on a high-definition set-top box, so as to realize synchronization of audio decoding and video decoding. Background technique [0002] Nowadays, the standard definition set-top box industry has been developing in full swing. With the improvement of people's living standards, standard definition programs can no longer meet the needs of people watching high-definition video and high-quality audio, and high-definition set-top boxes will definitely play an important role in the next industrial upgrade. Playing a small amount of high-definition program streams, the emergence of high-definition set-top boxes can meet the needs of some users to watch high-definition TV. But as time goes on, high-definition programs will surely occupy a major position in users' lives. [0003] In high-definition data services, ...

AI Technical Summary

Problems solved by technology

[0004] In order to improve the sound quality, many high-definition streams currently use the encrypted audio format, and the encrypted audio is difficult for general chips to decode, which brings technical difficulties to practical applications to a certain extent.

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